1. Field of the Invention
This invention relates to recoverable hollow articles comprising an inner member which is composed of an elastomeric material and which has been elastically deformed from its natural dimensions to a radially extended condition, and an outer restraining means which maintains the inner member in its extended condition but which can be treated to permit the inner member to recover towards its natural dimensions.
2. Summary of the Prior Art
French Patent Application No. 7,618,236 and the corresponding U.S. Pat. No. 4,070,746 (Evans et al. to Raychem) and copending U.S. application Ser. No. 586,901 (Krackeler et al. to Raychem) filed June 16, 1975, the disclosures of which are incorporated by reference herein, describe recoverable hollow artiles comprising an inner member, preferably of an elastomeric material, which is held in a radially extended condition by an outer restraining means, the inner member and the restraining means being secured together by means of a bond which can be broken to allow the inner member to shrink radially. Preferably the restraining means is capable of being peeled away from the inner member; the peeling process can be assisted by applying a solvent to the bond line. The restraining means may be composed of a frangible material which can be broken by means of a sharp blow, for example a rigid thermoplastic such as polyvinyl chloride. Alternatively the restraining means can have weakened portions such as score lines which enable it to be peeled away from the inner member, as for example a metallic tube which is spirally scored or serrated. The recoverable articles are useful for covering substrates, especially splices and terminations in electrical cables, e.g. mine cables.